The first objective is methodological. The studies that have been done on attachment have used a variety of techniques--interview with the mother, structured situations in the laboratory--and a variety of indices to measure attachment. In this study, we plan to compare data obtained from observations in the home, with data from an interview with the mother and from observations of structured situations in the laboratory. Underlying this methodological question is the conceptual issue of what are the most appropriate behavioral measures of this relationship. In addition to the methodological question we plan to examine the antecedents of the distinctive tie between mother and infant. Approximately half the sample will have been observed at six months. Several of the environmental variables observed at that time have been hypothesized to relate to later attachment, e.g., amount of kinesthetic stimulation and mother's responsiveness to baby's distress.